To find the distance between a pair of points, you just use the distance formula. Fortunately, it is a very easy formula to use!

Step 1: Remember that your sets of points are (x, y). For the distance formula, you are going to use the two x’s and the two y’s. Let’s begin with the x’s.

Step 2: Subtract x1-x2. Your x1 is 3 and x2 is 15. That means you will do 3-15, which is -12.

Step 3: Subtract y1-y2. Your y1 is 3 and y2 is 8. That means you will do 3-8, which is -5.

Step 4: As you can see from the formula, you now need to square each of these. This means you are going to multiply them by themselves. -12 x -12= 144, and -5 x -5 = 25. As you can see, we got rid of those pesky signs by squaring.

Step 5: Add! Add the two squares together. 144 + 25= 169

Step 6: Take the square root. `sqrt(169)` You get 13.

Yeah! You’re done. The answer is 13 is the distance between the two points. Whew!